Abstract:To solve the problem of unreliable monitoring accuracy of GNSS signals under the influence of environmental occlusion and multipath errors, the idea of variance expansion is introduced into the GNSS/accelerometer fusion filtering algorithm based on Huber’s weight selection iteration method, which adaptively adjusts the measurement noise of GNSS anomalies from the perspective of stochastic model, reduces the influence of GNSS anomaly observation on Kalman filtering measurement update, and improves the reliability of GNSS/accelerometer fusion deformation monitoring results. The results show that the improved fusion algorithm can significantly improve the accuracy of GNSS monitoring in a complex multi-path environment, and the RMS of deformation displacement obtained by its solution is within 1.8 cm in 3D direction, which can provide a reference for high-precision deformation monitoring in complex environments.